In recent years, in accordance with progress in a video generation technique and the like, it is required that a fine image is generated in real time for a computer game and the like. In NPL 1, a technique for eliminating tearing or stutter (stuttering) which is caused in a case where image generation becomes late for refresh timing of a display due to an increase in a load of image generation is described. With a method of NPL 1, an image data output device controls the refresh timing of the display, and thereby tearing or stutter is able to be eliminated.